The present technology relates to an imaging lens and an imaging apparatus using the imaging lens. Specifically, the present technology relates to a large-diameter imaging lens having approximately F2.0 that is suitable for a small-sized imaging apparatus such as a camera-equipped mobile phone using a solid-state imaging element.
Camera-equipped mobile phones and digital still cameras using solid-state imaging elements such as CCDs (charge coupled device) and CMOSs (complementary metal oxide semiconductor) have heretofore been known. In such imaging apparatuses, there has been an increasing demand for size reduction, and an incorporated imaging lens having a small size and a short total length has been also demanded. Moreover, in recent years, small-sized imaging equipment such as camera-equipped mobile phones have been reduced in size and a pixel density of imaging elements has become higher, so that models incorporating imaging elements having a high-pixel density of eight million pixels or more have been also popular. Therefore, it has been demanded that imaging lenses to be incorporated into such imaging equipment and apparatuses have high lens performance corresponding to the solid-state imaging element having a high-pixel density.
Meanwhile, in the imaging apparatus, a fine lens having a larger diameter has been demanded for preventing a decrease in sensitivity and an increase in noise of the imaging element caused by narrowing a cell pitch. An imaging lens made of four lenses is frequently used as such a small-sized and high-performance imaging lens (for example, see Japanese Patent Application Laid-Open Nos. 2009-265245 and 2010-049113).